A rigid ring $A$ and a rigid thin disk $B$ both made of same material, when gently placed on water, just manage to float due to surface tension as shown in the figure. Both the ring and the disk have same radius. What can you conclude about their masses?

A thin ring of radius $10 \mathrm{cm}$ is placed on a water surface. Calculate the force required to take away the ring from the surface of water. Surface tension of water $=0.07 \mathrm{N} {\mathrm{m}}^{-1}$

An annular disc of radius $r=10 \mathrm{cm}$ and $R=20 \mathrm{cm}$ is placed on a water surface, Calculate the force required to take away the plate from the surface of water. Surface tension of water $=0.07 \mathrm{N} {\mathrm{m}}^{-1}$

In figure $\left(a\right)$ given below shows a thin liquid film supporting a small weight equal to $5.0\times {10}^{-2} N$. What is the weight supported by a film of the same liquid at the same temperature in Figs. $\left(b\right)$ and $\left(c\right)$ ?

A circular ring has inner and outer radii equal to $r$ and $R$ respectively. Mass of the ring is $m$ It gently pulled out vertically from a water surface by a sensitive spring. When the spring is stretched $3.4 cm$ from its equilibrium position the ring is on verge of being pulled out from the water surface. If spring constant is $k$. Find the surface tension of water.

A glass plate of length $50 \mathrm{cm}$, breadth $40 \mathrm{cm}$ and thickness $5 \mathrm{cm}$ weighs $3 \mathrm{kg}$ in air. If it is held vertically with long side horizontal and the plate half immersed in a liquid, what will be its apparent weight? Surface tension of the liquid $=50\times {10}^{-2} \mathrm{N} {\mathrm{m}}^{-1}$